demos/texturing.cpp

   1 #include <cmath>
   2 #include <msp/graphics/simplewindow.h>
   3 #include <msp/gl/framebuffer.h>
   4 #include <msp/gl/matrix.h>
   5 #include <msp/gl/mesh.h>
   6 #include <msp/gl/meshbuilder.h>
   7 #include <msp/gl/texenv.h>
   8 #include <msp/gl/texture2d.h>
   9 #include <msp/gl/texturing.h>
  10 #include <msp/time/timestamp.h>
  11 #include <msp/time/utils.h>
  12 #include <msp/time/units.h>
  13
  14 using namespace Msp;
  15
  16 int main()
  17 {
  18         Graphics::SimpleGLWindow wnd(400, 400);
  19
  20         GL::Texture2D tex1;
  21         GL::Texture2D tex2;
  22
  23         unsigned char *data = new unsigned char[256*256*4];
  24         for(unsigned y=0; y<256; ++y)
  25                 for(unsigned x=0; x<256; ++x)
  26                 {
  27                         unsigned i = (x+y*256)*3;
  28                         data[i] = 255;
  29                         data[i+1] = (((x/32)+(y/32))&1 ? 255 : 0);
  30                         data[i+2] = 0;
  31                 }
  32         tex1.storage(GL::RGB, 256, 256);
  33         tex1.set_min_filter(GL::LINEAR);
  34         tex1.image(0, GL::RGB, GL::UNSIGNED_BYTE, data);
  35
  36         for(unsigned y=0; y<256; ++y)
  37                 for(unsigned x=0; x<256; ++x)
  38                 {
  39                         unsigned i = (x+y*256)*4;
  40                         data[i] = data[i+1] = data[i+2] = 0;
  41                         data[i+3] = (((x/32)+(y/32))&1 ? 255 : 0);
  42                 }
  43         tex2.storage(GL::RGBA, 256, 256);
  44         tex2.set_min_filter(GL::LINEAR);
  45         tex2.image(0, GL::RGBA, GL::UNSIGNED_BYTE, data);
  46         delete[] data;
  47
  48         GL::Texturing texturing;
  49         texturing.attach(0, tex1);
  50         GL::TexEnv texenv;
  51         texenv.set_mode(GL::DECAL);
  52         texturing.attach(1, tex2, texenv);
  53
  54         GL::MatrixStack::projection() = GL::Matrix::frustum_centered(0.2, 0.2, 0.2, 10);
  55         GL::MatrixStack::modelview() = GL::Matrix::translation(0, 0, -3);
  56         GL::MatrixStack::modelview() *= GL::Matrix::rotation(-45, 1, 0, 0);
  57
  58         GL::Mesh mesh((GL::TEXCOORD2, GL::TEXCOORD2,1, GL::VERTEX3));
  59         GL::MeshBuilder bld(mesh);
  60         bld.begin(GL::QUADS);
  61         bld.texcoord(0, 0);
  62         bld.multitexcoord(1, -0.2071, 0.5);
  63         bld.vertex(-1, -1);
  64         bld.texcoord(1, 0);
  65         bld.multitexcoord(1, 0.5, -0.2071);
  66         bld.vertex(1, -1);
  67         bld.texcoord(1, 1);
  68         bld.multitexcoord(1, 1.2071, 0.5);
  69         bld.vertex(1, 1);
  70         bld.texcoord(0, 1);
  71         bld.multitexcoord(1, 0.5, 1.2071);
  72         bld.vertex(-1, 1);
  73         bld.end();
  74
  75         wnd.show();
  76         float angle = 0;
  77         Time::TimeStamp last;
  78         while(1)
  79         {
  80                 for(unsigned i=0; i<4; ++i)
  81                 {
  82                         float *v = mesh.modify_vertex(i);
  83                         v[2] = 0.5+sin(angle)*0.1+cos(angle+i*M_PI/2)*0.7071;
  84                         v[3] = 0.5+cos(angle)*0.1+sin(angle+i*M_PI/2)*0.7071;
  85                 }
  86                 wnd.get_display().tick();
  87                 GL::Framebuffer::system().clear(GL::COLOR_BUFFER_BIT);
  88                 {
  89                         GL::Bind bind_tex(texturing);
  90                         mesh.draw();
  91                 }
  92                 wnd.swap_buffers();
  93                 Time::TimeStamp t = Time::now();
  94                 if(last)
  95                         angle += 0.5*((t-last)/Time::sec);
  96                 last = t;
  97         }
  98
  99         return 0;
 100 }